Sodium (Na) metal batteries are nowadays appealing due to high specific capacity and low cost. However, major caveats including severe Na dendrite growth, unstable solid electrolyte interphase formation, and poor mechanical robustness have hampered its practicability. In this report, a highly sodiophilic and conductive host harnessing hierarchical vertical graphene (VG) cultivator and Co nanoparticle/N‐doped carbon decorator (Co‐VG/CC) is designed to accommodate Na metal throughout a facile infusion route. The strong interaction between Co‐VG/CC and Na is realized by sodiophilic Co nanoparticle/N‐doped carbon hybrid, resulting in excellent structural stability of the electrode. The well‐regulated Na adsorption behavior and uniform stripping/plating mechanism is systematically investigated via theoretical simulation in harmonization with in situ/ex situ electroanalytical analysis. In consequence, as‐derived Na@Co‐VG/CC electrode effectively inhibits the dendrite formation, resulting in promising electrochemical performances in symmetric cell configuration (functioning at an elevated rate of 5.0 mA cm−2 under 5.0 mAh cm−2 for 280 h, delivering a high capacity of 6.0 mAh cm−2 at 3.0 mA cm−2 for 1000 h and maintaining an ultralong lifespan up to 2000 h). Meanwhile, assembled flexible Na metal battery full cell can sustain to work for 120 h, representing a great advance in practical energy storage applications.

Employing an Al foil current collector at the potassium anode side is an ideal choice to entail low‐cost and high‐energy potassium‐metal batteries (PMBs). Nevertheless, the poor affinity between the potassium and the planar Al can cause uneven K plating/stripping and, hence, an undermined anode performance, which remains a significant challenge to be addressed. Herein, a nitrogen‐doped carbon@graphdiyne (NC@GDY)‐modified Al current collector affording potassiophilic properties is proposed, which simultaneously suppresses the dendrite growth and prolongs the lifespan of K anodes. The thin and light modification layer (7 µm thick, with a mass loading of 500 µg cm−2) is fabricated by directly growing GDY nanosheets interspersed with Cu quantum dots on NC polyhedron templates. As a result, symmetric cell tests reveal that the K@NC@GDY‐Al electrode exhibits an unprecedented cycle life of over 2400 h at a 40% depth of discharge. Even at an 80% depth of discharge, the cell can still sustain for 850 h. When paired with a potassium Prussian blue cathode, the thus‐assembled full cell demonstrates comparable capacity and rate performance with state‐of‐the‐art PMBs.

No abstract

Developing new reactive pathway to activate inert C(sp3)−H bonds for valuable oxygenated products remains a challenge. We prepared a series of triazine conjugated organic polymers to photoactivate C−H into aldehyde/ketone via O2→H2O2→⋅OH→Cl⋅→Cl2⋅−. Experiment results showed Cl2⋅− could successively activate C(sp3)−H more effectively than Cl⋅ to generate unstable dichlorinated intermediates, increasing the kinetic rate ratio of dichlorination to monochlorination by a factor of 2,000 and thus breaking traditional dichlorination kinetic constraints. These active intermediates were hydrolyzed into aldehydes or ketones easily, when compared with typical stable dichlorinated complexes, avoiding chlorinated by‐product generation. Moreover, an integrated two‐phase system in an acid solution strengthened the Cl2⋅− mediated process and inhibited product overoxidation, where the conversion rate of toluene reached 16.94 mmol/g/h and the selectivity of benzaldehyde was 99.5 %. This work presents a facile and efficient approach for selective conversion of inert C(sp3)−H bonds using Cl2⋅−.

No abstract